A public warning system (PWS) for a 4G Long Term Evolution (LTE) network may be based on the warning message transmission messages as defined in LTE 3GPP specification 3GPP TS 36.413 Release 9 and the warning message delivery procedure as defined in LTE 3GPP specification 3GPP TS 23.401 release 9, and further relies on the LTE S1AP protocol procedures Write-Replace Warning Request/Response and Kill Request/Response.
As well, the Cell Broadcasting Service (CBS) has been used to inform users about an emergency situation arising in their geographic location(s) due to natural or man-made calamities. CBS thus provides a useful alternate communication channel for government agencies to let people know about emergency situations and ask people to stay away from danger zones. Similar systems are known by various names in different part of the world, such as Earthquake and Tsunami Warning System (ETWS) in Japan, Commercial Mobile Alert System (CMAS) in the USA, etc. PWS service or CBS is implemented at a Cell Broadcast Center (CBC). The CBC is in charge of receiving messages sent by a Cell Broadcast Entity (CBE). On reception of the messages from the CBE, the CBC formats the messages by adding certain parameters and forwards the messages to the Mobile Management Entity (MME) in a Long Term Evolution (LTE) network or the Base Station Controller (BSC) in a Global System for Mobile Communications (GSM) network. The MME or BSC forwards the warning messages to eNodeBs or NodeBs connected to them, so that the users camped on to the eNodeBs or NodeBs receive the warning message and hopefully stay away from the danger. The PWS is based on standards developed by ETSI and 3GPP, specifically 3GPP TS 36.413, 3GPP TS 23.401, and is based on an LTE S1AP protocol procedures, e.g., Write-Replace Warning Request/Response, and Kill Request/Response.
The purpose of the public warning system is thus to alert cell users within areas which are under threat due to natural or other calamities. The public warning system in a Long Term Evolution (LTE) network may have following components: cell broadcasting entity (CBE), cell broadcasting centre (CBC), mobility management entity (MME), and eNodeB. The public warning system may be devised with a view to alerting areas that are under threat due to potential earthquakes or tsunamis, etc.